[PATCH] efi_runtime: use memdup_user() as a cleanup

[Ivan Hu]

Got warning when upstreaming efi_runtime driver

drivers/firmware/efi/test/efi_test.c:269:8-15: WARNING opportunity for
memdup_user

Use memdup_user rather than duplicating its implementation
This is a little bit restricted to reduce false positives

Generated by: coccinelle/api/memdup_user.coc

Signed-off-by: Ivan Hu <ivan.hu at canonical.com>
---
 efi_runtime/efi_runtime.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/efi_runtime/efi_runtime.c b/efi_runtime/efi_runtime.c
index 594eccd..19f8103 100644
--- a/efi_runtime/efi_runtime.c
+++ b/efi_runtime/efi_runtime.c
@@ -284,14 +284,10 @@ static long efi_runtime_set_variable(unsigned long arg)
 			return rv;
 	}
 
-	data = kmalloc(setvariable.data_size, GFP_KERNEL);
-	if (!data) {
+	data = memdup_user(setvariable.data, setvariable.data_size);
+	if (IS_ERR(data)) {
 		kfree(name);
-		return -ENOMEM;
-	}
-	if (copy_from_user(data, setvariable.data, setvariable.data_size)) {
-		rv = -EFAULT;
-		goto out;
+		return PTR_ERR(data);
 	}
 
 	status = efi.set_variable(name, &vendor_guid,
-- 
1.9.1